ST. AUGUSTINE, Fla. -- Walk in to Kristin Harrington's second grade classroom at Palencia Elementary School and you will see students working in pairs on school iPads.

"If you learn on the iPad it's a lot funner because you have a lot of apps like Hungry Fish, or math or Tunetastic. You get to make your own movie," said second grader Hunter Riedle.

Today's lesson: Comparing and contrasting, the comprehension skill of the week.

"They are using their digital textbooks. They are using an app called Popplet, which is actually a free app if you use Popplet Lite, where they are able to create their own graphic organizers to compare and contrast which will later be turned in to a paragraph," Harrington said. "So it just makes it a little more fun, a little easier for them to use and more engaging for the students."

Palencia Elementary is the first school in the St. Johns County School District to go completely digital. Students at this school don't use any paper textbooks.

"I'd say within one to two weeks they were adapted to it and really like it," Harrington said.

Harrington said the possibilities are endless with digital textbooks. It's a video camera, a calculator, a QR code scanner and much more.

Principal Don Campbell said the students spend about a third of their day on the iPad. He calls it traditional learning with contemporary technology. They still use a pencil and paper, have a lot of dialogue and listen to the teacher.

But as with any technology he said there are downsides to having only digital textbooks.

"The internet may go down, power may go out, the battery may die. You might not be able to access a site you are looking for. All kinds of issues you find with technology we find those too here but they are no different than if the power were to go off when you were teaching," he said.

And then there's the cost.

"Right now this is a brand new school, so there was some money upfront and there were some capital funds," Campbell said. "What will it be like when we have to outfit all of the schools and all 32,000 students?"

Child psychologist Katie Falwell said while some educational apps have been proven to increase student's skills, others could be harmful.

"We look at MRIs and can actually see changes in the brain so they have a much shorter wait time, their impulsivity is higher," Falwell said.

Falwell said it typically takes three to five years to truly know the impact of using an iPad as a textbook.

"So right now our kids our guinea pigs. They have only been out 2 years on the market, the iPad has, so the jury is out on it. But my concern is our kids are going to become guinea pigs in the mean time where we really should be looking at in moderation rather than gung ho let's go all straight electronics, let's roll a dice and see what happens. That's concerning to me."